The present invention relates to a cable connector such as used with an RF cable for connecting a VCR (video cassette recorder) to a TV (television) receiver (e.g., a coaxial cable with connector plugs). Such a cable connector may also be used with an antenna cable for connecting an antenna to a television receiver or VCR.
A coaxial cable has a central conductor surrounded by a concentric outer conductor and separated from it by a dielectric material. The concentric outer conductor is a metallic shield generally made of braided copper or metal tape. A cable connector is attached to a coaxial cable to plug into a receptacle on a device.
Devices such as TV's and VCR's are regionally standardized. For instance, European color television broadcasts use the PAL (Phase Alternate Line) format and SECAM (Sequential Couleur a Memoire) format, unlike the United States and Japan, which use the NTSC (National TV System Committee) format. Specifically, the PAL format is used in the United Kingdom and Germany, while the SECAM format is used in France and Russia. Physical connectors used with one format are not necessarily compatible with physical connectors used with a different format.
Referring to FIG. 8, a prior art RF cable 10 with integral connectors includes coaxial cable 11 with a socket connector 12 on one end and a plug 14 on another end. Coaxial cable 11 also includes a conventional central conductor (not shown), an insulator (not shown), and a concentric outer conductor (not shown). A center pin 16 of plug 14 is electrically connected to the central conductor of coaxial cable 11. A sleeve 20 is electrically connected to the outer conductor of coaxial cable 11. Sleeve 20 is separated from center pin 16 by an insulator 18. An insulating cover 22 over sleeve 20 protects plug 14 from the environment and provides an insulated object for a user to grasp during plugging and unplugging. A portion of center pin 16 and a portion of sleeve 20 are exposed for making contact with corresponding portions of a receptacle 30.
Receptacle 30 includes a signal terminal 32 into which center pin 16 connects. Receptacle 30 also includes a grounding terminal 34 into which sleeve 20 connects. In this state, center pin 16 of plug 14 and sleeve 20 are elastically connected to signal terminal 32 and grounding terminal 34 of receptacle 30, respectively. An electrical connection between VCR 24 and TV 28 is created by socket connector 12 connecting with a receptacle 26 and plug 14 connecting with receptacle 30.
In the PAL format, an outer diameter D of sleeve 20 of plug 14 is a standard 9.525 mm, while in the SECAM format, an outer diameter D of sleeve 20 of plug 14 is a standard 9.0 mm. An inner diameter of grounding terminal 34 of receptacle 30 is also standardized to a dimension corresponding to an adequate elastic contact. Also, the depth of the exposed portions of center pin 16 and sleeve 20, and their mating parts in receptacle 30, have standardized dimensions.
Thus, when cable 10 is made for the PAL format, it can only connect a PAL format VCR 24 and a PAL format TV receiver 28. A PAL format cable cannot be used to connect SECAM format devices (VCR's and TV's) to each other nor can it be used to connect a PAL format device to a SECAM format device. Likewise, when cable 10 is made for the SECAM format, it can only connect a SECAM format VCR and a SECAM format TV. A SECAM format cable cannot be used to connect PAL format devices (VCR's and TV's) to each other nor can it be used to connect a SECAM format device to a PAL format device. Cables with connectors of the two formats are color-coded to prevent confusion caused by attempting to connect SECAM format devices using a PAL format cable and vice versa.
Referring to FIG. 9, a conversion connector 46 permits a PAL format cable to connect a PAL format VCR to a SECAM format TV. A PAL format cable 10 includes a coaxial cable 11 and a plug 14. A SECAM format TV 36 includes a receptacle 38 which is also in the SECAM format. Conversion connector 46 includes a center connection conductor 42 and a ground connection conductor 44. Outer diameter D (9.525 mm) of sleeve 20 of plug 14 is too large to fit inside an inner diameter N.sub.s of grounding terminal 40 of receptacle 38 of SECAM TV 36. Since a standard SECAM format plug has a sleeve with an outer diameter of 9.0 mm, N.sub.s is a value smaller than 9.0 mm by a prescribed amount so that an interference fit for good elastic contact can be made.
A special cable (not shown) having a SECAM plug on one end and a PAL plug on the other end can be used instead of a conversion connector 46 to connect two dissimilar devices.
Thus, when connecting devices with different formats, such as the PAL format and the SECAM format, it is necessary to have additional parts such as a conversion connector or a conversion cable. This increases the number of parts required to be manufactured and warehoused, making operations more complicated and raising costs. Furthermore, problems arise when trying to connect dissimilar devices using a SECAM format cable or a PAL format cable. The two formats are close enough that a user often believes that the cable should connect properly. The user may then try to force a fit, thereby damaging the cable or the receptacles or making a bad connection.